Teresa of Ávila Saint (1515–82), Spanish religious, mystic, and author of spiritual treatises. Having entered the Carmelite order at Ávila at twenty-two, Teresa spent the next twenty-five years seeking guidance in the practice of prayer. Despite variously inept spiritual advisers, she seems to have undergone a number of mystical experiences and to have made increasingly important discoveries about interior life. After 1560 Teresa took on a public role by attaching herself to the reforming party within the Spanish Carmelites. Her remaining years were occupied with the reform, in which she was associated most famously with John of the Cross. She also composed several works, including a spiritual autobiography (the Vida) and two masterpieces of spirituality, the Way of Perfection and the Interior Castle. The latter two, but especially the Castle, offer philosophical suggestions about the soul’s passions, activities, faculties, and ground. Their principal motive is to teach the reader how to progress, by successive surrender, toward the divine Trinity dwelling at the soul’s center. M.D.J.